Dobson is a great prospect, but the fact that one guy is still playing and another hasn't played in like a month+ makes this an unfair comparison. Dobson is front and center in people's minds, and ideas about Bouchard's game are informed more by months old hearsay and narrative than any kind of empirical proof. The best example: people talk about how slow Bouchard is, but Bouchard tested quite well at the top prospects game in terms of skating. In particular, he was second to only Dobson when it came to skating backwards. But that doesn't fit the narrative, so people ignore it.
This is not to mention that Bouchard was head and shoulders the better defenseman for the majority of the season. He had a historic season offensively in a better CHL league on a worse team. He was insanely dominant. We can't forget that just because he isn't playing anymore.
That's not to say that Bouchard is anywhere near the skater Dobson/Hughes/etc are. But I find that a lot of these criticisms conclude that Bouchard doesn't skate well enough to play like Dobson/Hughes/ etc in the NHL, so he's too slow. What they oftentimes don't evaluate is whether Bouchard skates well enough to play like Evan Bouchard in the NHL. And, hey, he probably needs to work on it. But not everyone is going to be a puck rushing defenseman. Not everyone needs to be.